Seven years ago, writer-director Lawrence Kasdan and his wife and sometimes writing partner, Meg, adopted a dog they named Mac from a shelter. Two years later, the pooch ran off into the Colorado wilderness after a mountain bike whizzing by startled him.

"The weather was terrible. The terrain was rough. We thought we had lost him," Kasdan relates of the incident that would inspire "Darling Companion," which made its local premiere at the San Francisco International Film Festival.

"After about 10 days, we were really getting discouraged and Meg said to a friend here in L.A. who was attached to the dog, 'I hate to tell you this, but I think we've lost Mac,' and the woman paused and said, 'No, you haven't. He's all right.' Meg said, 'What do you mean?' She said, 'I know he's going to be fine.' Meg said, 'We're really distraught about this. What are you talking about?' She said, 'I've never told you this, but I find things. I have an affinity for animals. I just know he's out there and you have to just keep looking.' "

Their friend was right. Mac reappeared after three weeks, and for a couple of years afterward, Meg Kasdan would tell the story of the missing dog and the pal who claimed to be psychic. Eventually, she suggested that the story was the perfect jumping-off point for a screenplay, the Kasdans' first joint writing effort since 1991's "Grand Canyon."

While one darling companion is, in fact, Freeway, the mutt Beth (Diane Keaton) finds on the side of the highway and brings home, much to the consternation of husband Joseph (Kevin Kline), the human relationships are more to the point. Beth and Joseph have been married for decades and take each other for granted. Their youngest daughter, Grace (Elisabeth Moss), finds love when she least expects to with veterinarian Sam (Jay Ali). Joseph's sister Penny (Dianne Wiest) has a new boyfriend, Russell (Richard Jenkins), who makes her happy but whom Joseph and Penny's son Bryan (Mark Duplass) distrust.

"We see the thing as being about a variety of companionships," Kasdan says, adding that when it came to casting his actors, "I wanted the best people, the best sort of feeling on the set. The subject matter is a lot about aging and mortality and about commitment. I think I was looking for people with character, people who are aware of the passing of time and what it means."

'Ruminative quality'

It is Kasdan's sixth film with Kline, who had one of his first starring roles in the filmmaker's 1983 Baby Boomer classic "The Big Chill" and went on to appear in "Silverado" (1985), "I Love You to Death" (1990), "Grand Canyon" (1991) and "French Kiss" (1995). The two men have remained friends over the years, although Kasdan says he and Meg were not thinking of Kline as they wrote the script.

"We didn't write with anyone in mind," he says. "The second you're finished, that's when you get to start thinking about that. That's the fun part. Immediately, we thought of Kevin. He's got a unique set of qualities. He's been very different for me in a lot of different roles. There's this feeling of intelligence and thought. He has a ruminative quality that you don't always get.

"Kevin has no vanity in him," Kasdan adds. "He's just easy. He's a very funny guy. He's good with other actors. He keeps everybody laughing. He loves to act, and that's contagious. Part of the reason we were able to get this amazing cast for no money is that they all wanted to work with each other. They all wanted to work with Kline and Keaton."

He is serious about the "no money" angle: The film marks Kasdan's first independent feature. The old Hollywood hand, the man whose screenplay credits include "The Empire Strikes Back," "Raiders of the Lost Ark" and "Return of the Jedi," and who has four Oscar nominations to his credit, three for screenwriting as well as a best picture nod for "The Accidental Tourist," never even considered shopping "Darling Companion" to the major studios.

"We just didn't think they'd do it," he says. "There is no evidence that they are making movies like this at all. I haven't seen a comedy come out of Hollywood that was as sort of gentle and as realistic."

40th anniversary

There is another factor, and that is age. Kasdan is 63. He and Meg celebrated their 40th wedding anniversary in November. Their film revolves around a couple of their generation who are similarly long married. In fact, five of the stars of "Darling Companion" are older than 60: Kline, 64; Keaton, 66; Wiest, 64; Jenkins, 65; and Sam Shepard, 68.

"People over 60 are not really the focus of the movies," Kasdan says. "For some reason, Hollywood doesn't want to deal with people over 60, and if they do, they're used as comic relief. They're doddering. They're demented. That's not really how 60-year-olds, for the most part, perceive themselves or live or act. The most amazing thing when you get to be 60 is you feel exactly as you did as when you were 30."

'Most satisfying work'

In the years since Kasdan's poorly received "Dreamcatcher" in 2003, a couple of his projects didn't get made. Kasdan did some writing for other people and he executive-produced a couple of films, but he never intended to be away from filmmaking this long.

"You turn around, and all of the sudden nine years are shot. It was not my intention at all. It was terrible," he says.

"It did one wonderful thing, though. I appreciated every aspect of the job again. I had been doing it pretty regularly for the first 25 years. I would write 'em and direct 'em, write 'em and direct 'em. It's the most satisfying work you can imagine, but you can get jaded, just like in a marriage, just like in the movie. When I got that layoff and came back, I had a new appreciation for every aspect of it.

"I don't see how it could have been a better experience for me. It was so satisfying, and the spirit on the set was so good. We had so much fun. I can't imagine how it could have been better." {sbox}